Python: Read File

By Xah Lee. Date: . Last updated: .

Read entire file

fileObject.read()

# Read entire file

import sys
import os

xpath = os.path.expanduser("~/xtest.txt")

xtext = "Alice was beginning to get very tired."

# write file, overwrite exsiting
xfile = open(xpath, "w", encoding="utf-8")
xfile.write(xtext)
xfile.close()

# s------------------------------

# open file
xfile = open(xpath, "r", encoding="utf-8")

# read whole file
xtext = xfile.read()
xfile.close()

print(xtext)
# Alice was beginning to get very tired.

Read one line at a time

# Read one line at a time

import sys
import os

xpath = os.path.expanduser("~/xtest.txt")

xtext = """one
two
three
infinity"""

# write file, overwrite exsiting
xfile = open(xpath, "w", encoding="utf-8")
xfile.write(xtext)
xfile.close()

# s------------------------------

# open file, read mode
xfile = open(xpath, "r", encoding="utf-8")

for xline in xfile:
    print(xline, end="")

# one
# two
# three
# infinity

xfile.close()

Read entire file as a list of lines

fileObject.readlines()

# read entire file as a list of lines

import sys
import os

xpath = os.path.expanduser("~/xtest.txt")

xtext = """one
two
three
infinity"""

# write file, overwrite exsiting
xfile = open(xpath, "w", encoding="utf-8")
xfile.write(xtext)
xfile.close()

# s------------------------------

# open file, read mode
xfile = open(xpath, "r", encoding="utf-8")

xlines = xfile.readlines()

for x in xlines:
	print(x, end="")

# one
# two
# three
# infinity

xfile.close()

Using with-statement

Alternatively, you can use with:

# example of opening file, using with

with open("c:/Users/xah/xtest.txt", "r") as f:
    for x in f:
        print(x)

When using with, you do not need to close the file. Python will close any file opened within it, when the with block is done.

2013-11-29 thank to Kurt Schwehr for showing me with.

Python, Read Write File